Grinder-head.



A. W. PUFFER 62 G. W. HAYES.

GRINDER HEAD.

APPLIOATION FILED MAE.1 6, 1908.

Patented Aug. 17, 1909.

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' suitable material, preferably cast iron.

UNITED STATES PATENT OFETQE.

ALVIN W. PUFFER, OF MEDFORD, AND GEORGE W. HAYES, OF WINCHESTER,MASSACHU- SETTS, ASSIGNORS TO PUFFER MANUFACTURING COMPANY, ACORPORATION OF MAINE.

GRINDER-HEAD.

To all whom it may concern:

Be it known that we, ALVIN W. PUFFER and GEORGE W. HAYEs, both citizensof the United States, and residents, respectively, of Medford, county ofMiddlesex, and State of Massachusetts, andof Winchester, county ofMiddlesex, and State of Massachusetts, have invented an Improvement inGrinder-Heads, of which the following description, in connection withthe accompanying drawings, is a specification, like letters on thedrawings representing like parts.

The present invention relates to a grinder head, and is embodied in arotating grinder of the kind which is used in connection with theprocess of surfacing or dressing marble slabs, and the like, the headbeing connected with a vertically rotatingmember of the ma chine whichin turn is connected with a movable overhanging arm, so that thegrinder, while rotating, can be manipulated by the attendant and movedabout over the face of the slab. During the grinding process, the faceof the marble is plentifully supplied with water, the vertical rotatingshaft of the machine to which the grinder is connected being commonlyutilized as a feed pipe, so that a stream of water is fed through themiddle of the grinder on the surface which is being dressed or polished.In a grinder of this kind, it is desirable, first, that there should beplenty of space around the actual grinding surface for the freecirculation of water second, a good distribution of the grinding surfaceso as to afford a firm support for the grinder when part of the grinderis moved past the edge of the slab upon which it is working and, third,a convenient means for connecting and disconnecting the grinder headfrom the rotating actuating shaft of the machine, for the reason that anumber of grinders having grinding surfaces of different qualities areused in polishing a single piece of material.

The grinder head embodying the invention comprises a skeleton frame inthe general form of a disk, this frame being made of any The frame isprovided with sockets to contain pieces of grinding material which arein the form of segments, it being practicable to form the six grindingmembers employed by casting an annular piece of emery, carborundum, orthe like, and cutting the said piece into six equal parts. The socketsfor the Specification of Letters Patent.

Application filed March 16, 1908.

'tribution of the cooling medium.

Patented Aug. 17, 1909.

Serial No. 421,345.

parts in the grinder head are the same in shape, and three of thesockets are arranged along the periphery of the head, substantiallyequally spaced, while the other three sockets which alternate therewithare transverse, so that the grinding members contained therein projectfrom the periphery inward toward the middle of the wheel. This gives agrinding surface to which the marble is exposed, when the head isrotating, which surface extends from the periphery of the wheelapproximately two-thirds of the dis tance to the center thereof and, atthe same time, affording plenty of space for the dis- The head mayfurther be made in skeleton shape, thus affording plenty of room forclamping nuts projecting through the walls of the sockets, so that theblocks of grinding material can not only be readily replaced, but canalso be adjusted from time to time to take up wear and to keep theaggregate grinding surface on an even level.

A further feature of the invention consists in a simple and easilyoperated attaching device for holding the grinder head on the actuatingshaft of the machine.

Figure 1 is a vertical section through a grinder head embodying theinvention, showing the lower portion of the actuating shaft of themachine; Fig. 2 is a plan view with a portion of the shaft of themachine shown in section above the top of the grinder head; and Fig. 3is a detail, in vertical section, taken on a plane transverse to that ofFig. 2.

The head a, which is generally circular in shape, consists preferably ofa skeleton casting provided with three sockets 1) arranged along theperiphery of the wheel and three sockets b which start from theperiphery and extend inward toward the middle. These sockets are all ofthe same shape and size, so as to be capable of containing grindingmembers 0 of emery or carborundum, or similar material, which membersare alike in size and shape and consequently interchangeable. The sixmembers may conveniently be made by sawing a single annular member intosix equal parts, this being a convenient way of getting the membersuniform in size and shape. The head a is in skeleton form, so that thewalls of the sockets b and b are exposed and the grinding members 0 can,therefore, be clamped in position by means of clamping members which areaccessible at the outside of the said exposed walls. As best shown inFig. 2, the clamping members consist of hardened steel thimbles (Zprovided with flanges (Z which rest against shoulders (1 formed inthewalls of the sockets, the said thimbles having bolts (Z screwedtherein and arranged to engage clamps or followers d which rest againstthe sides of the grinding blocks 0. The blocks, therefore, can readilybe inserted in the sockets and then clamped firmly in position, it beingobvious, moreover, that, as the blocks wear away, they can be adjustedin the sockets so as to project the necessary distance beyond the lowersurface of the grinding head itself. It will be seen that by thisarrangement the grinding surface, that is, the effectual grindingsurface while the head is rotating, extends a considerable distance fromthe periphery of the wheel toward the center, there being, at the sametime, ample space for the distribution of cooling liquid along thesurface which is being operated upon.

In order that the grinder heads may be readily attached to and detachedfrom the vertically rotating shaft A, each head is pro vided withupwardly projecting lugs a which are bifurcated to afford recesses a toreceive projecting members or trunnions A which project laterally fromthe shaft A, and when the trunnions A are dropped into the recesses a itwill be seen that the two parts are connected together so far as relatesto the rotating movement, and in order to keep them from endwisedisplacement, the lugs a are provided with bores or openings to re ceivea key a which is preferably in the form of a U-shaped rod, as bestindicated in Fig. 2.

Claims.

1. A grinder head comprising a skeleton disk provided with a pluralityof equally spaced recesses parallel to the periphery of said disk toreceive segmentally shaped grinding members and also with an equalnumber of recesses of the same shape and size as those parallel to theperiphery and located between them andextending from the peripheryinward toward the middle of the disk; and grinding members conforming inshape to and detachably secured in said recesses.

2. A grinding head comprising a skeleton disk provided with six recessessubstantially equal in sha e and size, three of said recesses beingequal y spaced apart and located parallel to the periphery of the head,and the other three recesses being located between the recesses firstnamed and inclined inward from the periphery toward the middle, theskeleton formation of the disk being such that the spaces between saidrecesses are accessible; blocks of grinding material contained in saidrecesses; and clamping devices having actuating portions accessible atthe outside of the walls of said recesses, substantially as described.

3. A grinding head comprising a skeleton disk having six recesses eachof which is shaped to conform to and adapted to contain a grindingmember formed by equally dividing into siX parts an annular block ofgrinding material, three of said recesses being equally spaced and lyingparallel to the periphery of said disk, the other three recessesextending inward from said periphery and means for adjustably clampingsaid grinding portions in said recesses, substantially as described.

4:. A grinding head having a grinding surface and a holder to retain thematerial of which said grinding surface is formed, combined withbifurcated lugs projecting upward above said holder to receivetransverse projections connected with the rotating shaft to be revolvedthereby, said lugs being provided with transverse openings and aU-shaped retaining wire, the ends of which are adapted to be inserted insaid openings in the lugs.

In testimony whereof, we have signed our names to this specification inthe presence of two subscribing witnesses.

ALVIN W. PUFFER. GEORGE W. HAYES. WVitnesses JAMEs J. MALoNEY, M. E.COVENEY.

